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[scrapdaddy]

Here's a picture of the gears. It doesn't look like the (adapter) in the center of the plastic gear could be pressed out without damaging the gear.



The brass gear needs to have the groove machined in it so the cover can bolt down flat. Notice the groove in the plastic gears.

I don't have any of the newer style gears to compare.

 

[RUSH55]

Hey Rush,

Do you need any of those parts to get one going? Let me know I've got some spare parts in the bins.

Scrap, the only thing I need at the moment is an adapter to fit the other gear I have, or another gear altogether (with an adapter or square cut like we’ve been seeing). If you think you have something you wouldn’t mind parting with - otherwise I can pick up this gear from Specter.

 

[scrapdaddy]

Here's a question, could a guy cut out the newer style plastic gear to match an older style adapter(wedge) and bond them together?

Let me pull out all my junk and see exactly what I have.

 

[WarDamnEagle]

Having read this thread a couple of times as well as a couple of others, it looks like I can remove the access panel and pull this assembly without removing the glass? Maybe you need to wedge the glass in place somehow if you pull the entire regulator assembly? Apparently the tailgate isn't working on the pig I just purchased and I want to investigate but I don't want to get into a situation where I can't leave it "as is" if necessary and it would be preferable if "as is" is with the window rolled up.

Also can you get to the terminal block from the access panel with the tailgate and glass in place? If so then I assume I can jumper out the safety switch to see if that is the problem; again without removing glass etc.

Will be another week before I get my hands on it so just gathering as much knowledge as I can at this point. Thanks!

 

[scrapdaddy]

War Eagle,

You'll have to pull the two small clips that hold the lower glass track to the two arms. The arms are attached to the whole motor and gears assembly. You could leave the glass hanging out the end of the tailgate (supported) and then remove the guts of the tailgate. The glass would have to be slid back down in order to close the tailgate and with no way of getting back up properly until you reinstalled the motor and gears.

 

[WarDamnEagle]

War Eagle,

You'll have to pull the two small clips that hold the lower glass track to the two arms. The arms are attached to the whole motor and gears assembly. You could leave the glass hanging out the end of the tailgate (supported) and then remove the guts of the tailgate. The glass would have to be slid back down in order to close the tailgate and with no way of getting back up properly until you reinstalled the motor and gears.

Can you just access the tailgate access panel from the inside with the tailgate and glass up or is that not possible?

 

[RUSH55]

You might need some help. We had a couple people each time doing various tasks - holding the safety switch, eyeballing the window position, turning the key switch on the tailgate or running the toggle switch on the dash. Neither window holder was held solidly in place, so we were easily able to remove the window and holder separately. It was suggested that before reinstalling the window that you beat it into the holder with a rubber mallet to seat it into the rubber strip as deep as possible. Didn’t end up doing that, but did find that it’s pretty important for the window holder to be centered on the window.
If you end up needing to remove the clips, thoroughly soak them in your favorite penetrant. Tap them out with a hammer and punch if you have to, but be careful to try not to break the tabs if possible. They’re another one of those items that would nice to have extras of.

 

[RUSH55]

Can you just access the tailgate access panel from the inside with the tailgate and glass up or is that not possible?

It’s possible, but you won’t be able to perform any maintenance. The window is totally reliant on the motor being in place to hold it up.

 

[WarDamnEagle]

It’s possible, but you won’t be able to perform any maintenance. The window is totally reliant on the motor being in place to hold it up.

So in the case of a stuck up window; I assume you can remove the panel from the inside, remove the assembly and gently let the window go down into the tailgate (with help of course)? Otherwise how do you get the damn thing open?

Apologies for all the questions; will probably be easier once I can see it in person.

 

[scrapdaddy]

So in the case of a stuck up window; I assume you can remove the panel from the inside, remove the assembly and gently let the window go down into the tailgate (with help of course)? Otherwise how do you get the damn thing open?

I've never had to preform that one, but yes pretty much your only option. Bandaids, get lots of bandaids.

 

[RUSH55]

Yeah, remove the panel and start prodding around to see what’s going on. If the window won’t roll down, check your voltage at the junction. There’s a whole chain of electrical supply before it even reaches the motor, so that’s a good place to start. If the motor runs, but the window doesn’t move, that’s an indicator that the plastic gear is broke.

While you’re in there, you can spray down all of the parts associated with the opening handle and latches with your penetrant of choice.

 

[WarDamnEagle]

Thanks everyone. The first thing I ordered when I knew this deal was going through was every FSM I could find on SOR including the wiring diagrams.

 

[RUSH55]

Most everything in the circuitry is pretty simple. The tailgate motor however, has a fuse, breaker, relay, switch(es), junction block. When I set to get mine going several years back, pretty much everything in the chain was inoperable.

 

[bobm]

You'll hear the motor if it works. I took my glass out with it and the tailgate up. By myself. Bandaids lots of bandaids. Is possible

 

[WarDamnEagle]

Finally got around to looking at this today. The solid blue wire that carries 12v from the relay to both switches (and across the terminal block) is only reading 4.6v. I haven't gone upstream yet to check voltages but I'm guessing a partial ground on a wire somewhere. There is a very noticeable "click" in the dash area when you press the dash switch up or down momentarily. I assume that is the relay making contact. The dash switch is probably ok as I get the same 4.6v to the motor, up or down, when pressing the switch.

Will have to investigate further.

 

[roadstr6]

Glad to see this thread. I’ve got to dig into the tailgate on Bucky. Right now I have the guts out and I just prop up the glass with a 2x4 when I need it up and pull it out when I need to drop the gate.

 

[WarDamnEagle]

Kudos to Gary Schmauch for making this diagram. Much simpler to follow than the FSM wiring diagram.

So referring to this diagram, I lifted the LW and LB wires from the terminal strip which go straight to the motor (LW up and LB down). Using a 12v source straight from the battery I touched each wire individually and the motor gives the slightest "grunt" (only way I can describe the sound as it's not a click). Unfortunately that's all I get. Interestingly when touching the "up" wire the 12v lead sticks to the wire (like it wants to weld to it). I only left it on for a second but had to jerk it off. It doesn't do that or at least not nearly to the same degree when I touch the down wire. The window is all the way up.

So either the window is frozen in place and won't move or the motor is shorted. I'm leaning towards shorted motor at this point.

Previous owner said it was working fine until very recently. As part of the deal he tried to get it repaired and his mechanic diagnosed it as a bad motor. Maybe he was correct.

 

[J Mack]

his mechanic diagnosed it as a bad motor.

Could be bad motor or locked up gear box.

To test your DC motor, touch the leads of the ohmmeter to the white and one of the blue leads of the motor. The meter's screen should indicate a low resistance (somewhere between 10 and 30 ohms) repeat for the other blue lead.

To check motor function you’ll want to ground the white wire and apply positive 12volts to one of the blue wires at a time for up or down.

 

[WarDamnEagle]

Could be bad motor or locked up gear box.

To test your DC motor, touch the leads of the ohmmeter to the white and one of the blue leads of the motor. The meter's screen should indicate a low resistance (somewhere between 10 and 30 ohms) repeat for the other blue lead.

To check motor function you’ll want to ground the white wire and apply positive 12volts to one of the blue wires at a time for up or down.

Thanks. As described above, I already applied 12v to both leads and got no movement. The W/B wire has a good ground.

I just went back down and lifted all the motor leads. I get good continuity on LB wire but nothing on the LW wire. Pretty sure it's a bad motor.

 

[WarDamnEagle]

They still make the junction for the tailgate, I just bought one from toyota when I redid my tailgate.

Part Number 82670-30020 Block Assembly

FWIW this terminal strip is still available.

Also wanted to add some photos for posterity.

NOS “older” style gear set mentioned early in this thread:

“Newer” style gear set that I just pulled from my ‘77

And both sets side by side. The E clip shown with the NOS gear set was sourced locally by me. Not sure if it’s the same size as OEM but it seems to be working.